1. Technical Field
The present invention relates generally to logical circuits, and more particularly to a test circuit having cascaded pass gate devices and associated methods for evaluating pass gate performance.
2. Description of the Related Art
Pass gates (or “transmission gates”) are a common building block in logical circuits. For example, pass gates to provide access to storage elements in memory circuits, to implement branches paths in multiplexers/demultiplexers and to provide isolation of latch and other outputs with a lower device count than alternative tri-state and strict unidirectional logic implementations.
It is therefore desirable to provide a test circuit and method for measuring pass gate rise time and fall time performance under operating conditions that are as close to actual circuit loading conditions as possible. It is further desirable to provide such a circuit that can measure rise and fall times independently.